House Washing Cardiff

What Is Actually Growing On Your Walls

Stand close to a dirty wall and the problem is obviously alive. The green film on a shaded gable is algae. The grey and orange discs are lichen, and lichen grips hard enough to etch soft mortar and the top coat of render. The black speckling on white render is mould. None of it is dirt in the ordinary sense, which is why a brush and a hose put it straight back within a few weeks.

Cardiff speeds all of it up. We sit on the wet side of the country, the winters rarely get cold enough to kill anything off, and the prevailing south-westerly weather drives moisture onto one face of every building. That is why a house in Rhiwbina is clean across the front and green down the side. Washing a house here is a biology problem before it is a cleaning problem.

Why It Is Worth Doing

• It changes how the house reads from the pavement. Green streaking under a gutter joint or down a shaded gable is the first thing anyone sees, and it makes sound render look neglected.
• It keeps the wall dry. Algae and lichen hold water against the surface, so the wall dries slowly after rain and takes more frost damage in a cold snap.
• It protects the finish. Lichen roots into the top coat of render and into soft lime mortar, and the longer it sits the more of the surface comes away with it.
• It stops faults hiding. Heavy growth covers hairline cracks, blown render and failed pointing until they turn into a repair bill. We tell you what we find while we are on the wall.
• If the house is going on the market, it is the cheapest thing you can do before the photographs are taken.

Soft Washing Is How Walls Get Cleaned

Soft washing means cleaning with chemistry and dwell time instead of force. We apply a biocide solution at roughly the pressure of a garden hose, leave it to work into the surface, then rinse at that same gentle pressure. Heavy growth gets a second application rather than more pressure.

The difference shows months later. A lance knocks the visible green off and leaves the roots in the render, so it is back within a season. A soft wash kills the organism, and the residual biocide carries on working after we have packed up. Soft washed render keeps lightening for two to three weeks, so do not judge the result on the day we finish.

Runoff is the part that gets skipped. Beds and planting against the wall are soaked with clean water first so they take up less of anything that drifts, then sheeted where they sit tight to the brickwork, then rinsed again at the end. We keep the wash away from ponds and dilute anything that reaches a gully. The mix is set for the substrate as well, so painted masonry never gets the same strength as a hard silicone render.

Why A Pressure Lance On A House Is A Mistake

A driveway is a solid slab. A wall is layers, joints, seals and cavities, and water under pressure finds all of them. These are the failures we get called out to fix.

• Render, including K Rend and other through-coloured silicone renders. A lance strips the thin coloured top coat and leaves a permanent pale patch. On sand and cement render it opens hairline cracks and drives water behind the coat.
• Pebbledash. The stones sit on a thin bedding coat. Pressure takes them off in patches and no repair ever matches.
• Painted masonry. Masonry paint chalks as it ages. A lance takes it back to bare wall in seconds and turns a clean into a repaint.
• Cladding and timber boarding. Water forced up under the laps sits behind the boards where nothing dries it.
• uPVC frames and seals. Close range pressure scars the plastic and lifts the mastic, and the scarring then holds dirt for good.
• Brick. Older Cardiff terraces are often lime pointed, and lime is softer than anything modern. It rakes out of the joints under a lance, and repointing costs many times a house wash.

Every Surface On The Outside Of Your House

Walls are only part of the job. Render, pebbledash, brick, stone, painted masonry, cladding, timber boarding, uPVC fascias, soffits, downpipes, window frames and a conservatory roof all come off the same setup on the same visit. Each one takes a different mix and a different dwell time, which is the whole reason one machine setting does not go over all of them.

Brick and stone are soft washed too, because the mortar is the weakest part and the growth sits in the joints. Painted masonry gets a weaker mix, a shorter dwell and a test patch out of sight first. Cladding, uPVC fascias, soffits and frames are hand washed rather than sprayed, so the corners and the mastic lines actually come clean.

What We Turn Up With, And What Stays Off The Wall

Precision does far more of the work here than power. The machine that runs at full pressure on your driveway is dialled right down for the wall above it, and on most house washes the lance never comes off the van. A low pressure applicator puts the solution on, and the pump is there to move water, nothing else.

Hot water earns its keep at ground level, on oil marks, on a rendered plinth or on a greasy path, but heat is not what shifts algae off a wall. Dwell time is. We would rather leave a solution on for another twenty minutes than turn anything up.

We have been washing houses across Cardiff and South Wales since 2019, working out of a unit in Cardiff, so most of the city is a short run for us. If an elevation is heavy enough to need a second visit to finish properly, you hear that at the quote rather than on the day.

How A House Wash Runs, Step By Step

1. Survey and quote. We walk every elevation and identify the substrate before pricing, looking for blown render, loose pebbledash, failed pointing and chalky paint. Anything that needs repair before a wash, we say so then.
2. Protect the property. Planting is watered and sheeted, windows and trickle vents are closed, and meter boxes, sockets, alarm boxes and light fittings are covered.
3. Apply and dwell. The solution goes on from the bottom upwards so no clean streaks form through the dirt, then dwells for 15 to 30 minutes depending on the growth. It is never left to dry out in direct sun.
4. Rinse down. A gentle top down rinse at low pressure carries everything off. Two storeys are reached with extending poles from ground level, so nothing leans on your gutters or your conservatory.
5. uPVC and detail. Fascias, soffits, downpipes, frames, sills and any conservatory roof are hand cleaned and rinsed clear.
6. Walk round with you. We rinse the paths, driveway and beds, then walk the property with you before loading up. Anything you are not happy with gets redone while we are still there.

How Long It Takes And What It Costs

A mid terrace in Canton is normally a half day. A three bed semi in Whitchurch is most of a day. A large detached in Cyncoed with a conservatory and tight side access takes a full day, and heavy growth on one elevation can need a short return visit.

Price moves on the number and size of the elevations, the height, how heavy the growth is, how tight the side access is, and whether the uPVC, gutters and roof go in at the same time. As a rough guide most Cardiff house washes fall between £200 and £600, with small terraces below that and large detached properties above. Treat those figures as indicative. You get a real price once we have seen the house.

How Long The Result Lasts

Expect two to four years before green shows again, and expect the shaded north-facing elevation to go first. Houses under trees or backing onto fields pick it up quicker, while an exposed south-facing frontage can hold for five years. The second wash is always the easier one, because there is no built up layer to get through.

House Washing expertise across Cardiff and South Wales

We wash houses in Roath, Penylan, Cyncoed, Lisvane, Llanishen, Whitchurch, Rhiwbina, Radyr, Llandaff, Canton, Pontcanna, Grangetown, Splott, Rumney, Llanrumney and Cathays, and we cover Barry, Newport and the rest of South Wales from the same base. The work changes with the street. Painted Victorian frontages in Pontcanna need a gentle mix and a test patch. Pebbledash semis in Rumney need pressure kept off them completely. Rendered newer builds in Lisvane and Radyr go on the north gable first, so that elevation gets the longer dwell.

Ready when you are: arrange your house washing quote

Call or text 07576 128903, or email Liamdunn2406@outlook.com. Send a photo of the worst elevation with it and we can usually give you a sensible range before we visit. We answer seven days a week from 7:00 to 21:30 and work out of our base in Cardiff. Our Google rating is 5.0 from five reviews, all five stars.

If the walls are being done, price the roof, gutters, driveway and patio at the same time. Same access, same setup, one booking, and it comes out cheaper than having each of them back separately.